The present invention generally relates to fluid treating and, more particularly, to apparatus and methods which are especially adapted for providing improved treatment of fluids. Although capable of other important uses, this invention finds advantageous utility in the treatment of water to remove therefrom polyvalent metal ions such as calcium and magnesium by the exchange of sodium ions for such polyvalent metal ions and, by means of the same treating medium, namely, finely subdivided ion exchange resin particles, also provides the removal of chlorine, hydrogen sulfide, iron, including colloidal iron particles, bacteria and other taste and odor forming contaminants from water being treated in accordance therewith.
In the field of fluid treating, and particularly in the field of treating water for industrial, commercial, and domestic use, a number of systems have been proposed, some or all of which have certain undesirable characteristics, drawbacks or disadvantages associated therewith.
In the past, water softeners have been proposed wherein various electric timers or the like have been utilized to indicate the need for regeneration and to initiate such regeneration. These devices are, of course, not responsive to use and, as such, will trigger regeneration at fixed time intervals irrespective of whether the ion exchange material is exhausted. Still other water softeners have operated strictly on a manual basis, with indications of the need for regeneration of the ion exchange medium being indicated strictly by subjective reaction of the water user to the apparent softness, flavor, or other characteristics of the water then being used.
Certain other prior art water softeners have been characterized by the presence of an unduly slow regeneration cycle, caused either by the amount or nature of the ion exchange material or by other factors which tend to require an increased residence time in contact with the brine for regeneration. Still other water softeners of the prior art have used ion exchange materials which were unduly restrictive of water flow and hence were characterized by large pressure drops thereacross, which required long residence times and accordingly, large physical dimensions, or which simply required large quantities of ion exchange material to insure the activity over a reasonable period of time and to insure that an adequate job of softening could be done in the presence of relatively high flow rates.
The present invention overcomes the undesirable characteristics, drawbacks and disadvantages of the prior art by providing a fluid treating apparatus and method which employ finely divided surface active particles arranged in a loose bed and confined within a treating tank by means which prevent the escape of such particles but which, at the same time, permit fluid flow therethrough at a high rate and with a minimum pressure drop. In this regard, an important embodiment of the present invention is directed to a water treating device and method which employ fine mesh ion exchange resin particles to provide hardness and contaminant removal to an extent which was heretofore thought to be unachieveable. In this regard, an important aspect of the present invention involves the discovery that fine mesh cation exchange resin particles of below 50 mesh size, and preferably 100 to 200 mesh or smaller, measured on a dry basis, will, in addition to providing hardness removal at an extremely high rate of exchange, also provide for removal of chlorine, hydrogen sulfide, iron, including colloidal iron particles, bacteria and other taste and odor forming contaminants.
Another feature of the present invention involves the conjoint use of dual loose particle beds of ion exchange material, arranged in series, with aggregate particles in one bed being specially adapted to provide relatively inefficient ion exchange when the flow of water therethrough is in one direction and relatively efficient ion exchange when the flow of water therethrough is in the opposite direction, such arrangement providing an efficient and economical means for eliminating so-called reverse exchange in a water softener system wherein service flow through the bed of ion exchange material take place in one direction and both regeneration and rinsing take place in the opposite direction.
Another aspect of the present invention involves the provision of an apparatus for treating water which receives flow of untreated water, circulates that flow of untreated water through an ion exchange bed, and then returns the flow to a water tap or other outlet. In particular, this apparatus is so constructed that, after treatment of a given volume of water, the apparatus automatically switches to an ion exchange regeneration and rinse or reverse flow mode, whereby the ion exchange material is treated with brine to replenish its ion exchange capacity and then rinsed with fresh water.
Another aspect of the present invention is the construction and arrangement of a regeneration supply system wherein a measured quantity of regenerant fluid such as, for example, brine, is held in a supply tank for positive and rapid feeding to the ion exchange or treatment tank during regeneration, and wherein the supply of such regenerant in the tank is then replenished with a predetermined volume of freshly made regenerant, without action or attention by the operator or user.
Another feature of the present invention is the provision of an apparatus for treating water wherein all operation of that apparatus takes place entirely mechanically and fluidically, that is, an apparatus which does not require the presence of electrical or other external control signals in order to begin or continue operation, or to initiate or complete the regeneration cycle, all switching being done by fluid forces inherent in the static water pressure and under the influence of forces created by or during the flow of water.
Another feature of the present invention is the provision of an apparatus for treating water which utilizes a bed of fine mesh ion exchange resin particles which bed functions to collect particulate contaminants during service flow and is characterized by improved flushing properties as a result of increased porosity during regeneration thereof.
Another feature of the present invention is the provision of an apparatus for treating water utilizing a bed of fine mesh ion exchange resin particles which apparatus is characterized by regeneration and rinse cycles of short duration, particularly when compared to commercially available water softeners of conventional design and which utilizes substantially less water for rinsing and regeneration than is required by such conventional water softener devices.
It is, therefore, an important object of the present invention to provide an improved fluid treating apparatus and method.
Another object of the invention is to provide a fluid treating apparatus which includes a bed of finely subdivided ion exchange particles, arranged in a loose bed form and confined within a treating tank by means preventing the escape therefrom but permitting water flow therethrough at a high rate with minimum pressure drop.
Another object is to provide a novel method of removing chlorine, hydrogen sulfide, iron, including colloidal iron particles, bacteria, other taste and odor forming contaminants, and other foreign materials from a treated fluid such as water, and to provide an apparatus for carrying out this method.
Another object is to provide a fluid treating apparatus for water or other fluids which includes a treatment tank having therein a first bed of aggregate particles of a very fine subdivided particle size and a second bed of aggregate particles arranged in series therewith and adapted to provide relatively inefficient ion exchange when the flow of water therethrough is in one direction and relatively efficient ion exchange when the flow of water therethrough is in the opposite direction, such beds being separated from each other and constructed and arranged so as to prevent reverse ion exchange in service flow following regeneration of the beads.
Another object is to arrange such dual beds so that they may be manufactured and sold as a single unit, in prepackaged form, or otherwise.
Another object is to provide a water softener or other fluid treating apparatus which is characterized by the use of dual beds of ion exchange materials arranged so as to provide for complete treatment of water flowing therethrough, as well as to reduce pressure drop thereacross to a minimum.
Still another object is to provide a fluid treating apparatus having means for confining a loose bed of aggregate ion exchange particles to a desired area within a treatment tank, and having means permitting expansion and contraction of the bed of particles as their ion exchange capacity is depleted and replenished.
Another object of the invention is to provide an apparatus which includes means for feeding brine or other regenerating fluid to the ion exchange material area under positive pressure from the water supply being softened.
Another object is to provide an apparatus having a large brine make-up tank and means associated therewith for selectively premeasuring a desired volume of brine for passage through and regeneration of the ion exchange material under controlled conditions.
Another object is to provide such an apparatus which includes means for selectively measuring all or a portion of the fluid flow therethrough, and for using such flow measurement as a means for determining the time at which regeneration of the ion exchange material is initiated.
Another object is to provide an apparatus which includes a number of valves for controlling fluid flow, with the valves being arranged so as to be biased to a closed position or permitted to be opened solely in response to the fluid pressure acting on such valves.
Another object is to provide a fluid treating device which includes a novel arrangement of fluid treating tanks wherein a bed of finely subdivided ion exchange material may be confined for effective use.
Another object is to provide a fluid treating apparatus which includes a novel apparatus for transferring a measured quantity of brine from a storage or make-up area to a measuring or metering area and thence to the treating area for regeneration of the brine.
Another object of the present invention is to provide a fluid treating apparatus which utilizes ion exchange resin particles which apparatus is characterized by reduced rinse water and regenerant requirements.
Another object of the present invention is to provide an improved method and apparatus for treating fluids wherein particulate contaminants contained in the fluid are collected in a bed of fine mesh fluid treating materials wherein flushing of collected particulate contaminants from such bed is improved by selective size reduction of the fluid treating materials resulting in increased porosity in the bed.
These objects and other objects and advantages of the invention are accomplished by providing fluid treating apparatus which includes means for confining a loose bed of very finely subdivided ion exchange aggregate particles to a fluid treating area, means for causing fluid to flow through such area for treatment, means for permitting storing and making up a supply of fluid for regenerating the ion exchange material, and means for passing a predetermined amount of regenerating fluid through the treating tank after treatment of a predetermined amount of water, with regeneration taking place after treatment of a predetermined quantity of fluid in the apparatus.